What is it for? Just for installer?
@k07n: Yes. If you set your permissions correctly on the webserver, apply the HTTP_MOD_REWRITE parameter and copy htaccess.txt to .htaccess then the only warning you receive from the installer is that it can't determine the server software version but it may be possible to continue (which it is!). I should also add that I didn't include: fastcgi_intercept_errors on; in my server configuration block. I have this in my NGiNX http block as a global switch.
@netcarver: Thank you for the kind words. I may not post frequently but I try to make what I write useful to others.